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GF40.15-P-0001-05TRU Tire Pressure Monitor (TPM), Messages Relevant to Operation



GF40.15-P-0001-05TRU Tire pressure monitor (TPM), messages relevant to operation
- with CODE (470) Tire pressure monitor (base)
- with CODE (494) USA version


Messages relevant to operation in the multifunction display (A1p13) of the instrument cluster (A1) indicate to the driver that the air pressure in at least one wheel is changing or has changed. The messages ensue in "yellow" (information messages) or in "red" (warning messages).

The tire pressure monitor warning lamp (A1e66) in the instrument cluster is actuated in parallel with the warning messages ("red").

Messages relevant to operation are stored in the TPM [RDK] control unit (N88) with an event code.

The messages relevant to operation describe a regular operating condition. In the event of complaint there is no reason to exchange system components.





Message relevant to operation (soft warning with yellow display)

Information message
If the air pressure drops for more than 12 minutes (in one wheel or several wheels) by 0.25 bar under specified pressure adjusted by the driver and stored in the TPM [RDK] control unit, this is displayed in the multifunction display.

The due pressure correction is pointed out after the end of the journey (circuit 15 "OFF"). As a result the driver is requested to check the tire inflation pressure in the wheels, to correct the pressure if necessary and then reactivate the TPM system.

This message is self-acknowledging and goes out after 30 seconds.





Negative feedback of plausibility check after filling detection (soft warning with yellow display)

A plausibility check of pressure values is carried out as follows:
^ All the tire pressures are above the minimum pressure specific to the model series.
^ The difference between the largest and smallest pressure value is a maximum of 1.5 bar.
^ The pressure difference on an axle is a maximum of 0.5 bar between the right and left.
^ The rear axle pressures may only deviate by a maximum of 0.5 bar from the average front axle pressure.





Warning message (hard warning with red display)
A rapid pressure loss (more than 0.2 bar/min) has been detected in one wheel.

In addition the tire pressure monitor warning lamp in the instrument cluster is actuated.

The driver is urged to stop the vehicle immediately and to check the relevant tires for any foreign bodies which may have entered.

To make the vehicle safe to drive the spare wheel is to be fitted if necessary or TIREFIT tire repair kit used

Replace the corresponding TPM wheel sensor after TIREFIT is used.





Warning message (hard warning with red display)
A pressure loss of more than 20% or 0.5 bar/min has been detected.

In addition the tire pressure monitor warning lamp in the instrument cluster is actuated.

The TPM [RDK] control unit has stored the tire inflation pressure, in each case as a specified pressure to be monitored.

A warning message is also displayed with circuit 15 "ON" after correcting the tire inflation pressure in the workshop.

The TPM system must be reactivated.

The TPM system is activated with an increased tire inflation pressure (approx. 3.5 bar) on new vehicles at the plant.

To make the vehicle safe to drive the spare wheel is to be fitted if necessary or TIREFIT tire repair kit used

Replace the corresponding TPM wheel sensor after TIREFIT is used.





System message (soft warning with yellow display) after preceding warning message

Possible cause:
If a "red" warning message has been output, the "yellow" system message opposite is displayed when the ignition is "ON" (circuit 15) as long as the TPM system has not been reactivated. In a parallel operation the system activates the tire pressure monitor warning lamp in the instrument cluster.





System error message
Here wheels without TPM wheel sensors have been installed.





System error message
Here the TPM system is switched off due to a serious fault.

The TPM system is faulty.





System error message
The TPM system is temporarily inactive.

Possible cause:
^ over/undervoltage
^ interference transmitters





Operation feedback after reactivation
The driver has carried out reactivation via the operating menu in the instrument cluster.